1. Technical Field
The invention relates generally to masking to protect sensitive areas or areas which do not require application of or removal of coatings adjacent other areas where it is desired to apply or remove such coatings. More particularly, the invention relates to a masking material formed of a removable pressure sensitive adhesive. Specifically, the invention relates to a hot melt pressure sensitive adhesive which is easily removed by hand.
2. Background Information
Historically, masking has been utilized on aircraft, automobiles, equipment, rigs, ships and other structures to protect sensitive areas or areas not requiring cleaning, removal of a coating, or application of a coating from abrasive blasting, chemical stripper, new coatings, solvents or other exposure. This masking has been achieved by using a combination of tapes, hot glue, masking devices or sheet material. These traditional masking devices are time consuming in their application and removal and may or may not be adequate in their protection capabilities. In addition, they are typically rather expensive.
For example, it is generally difficult to remove hot glue, which must normally be chipped in multiple pieces from the surface that it was masking. In addition, hot glue embeds itself in tight places such as hinges, again compounding the difficulty of removal. Furthermore, adhesive tapes used in abrasive blasting generally do not have sufficient adhesion to withstand the blasting process to its edges even at low pressures such as 25 psi. Because of this drawback of such adhesive tapes, it has been required that hot glue be used to hold the edges of the adhesive tape down. Thus, abrasive blasting such as that used to depaint aircraft and the like requires the application of such adhesive tapes, which are typically rubberized, as well as the hot glue, thus making a costly and labor intensive masking device.
Thus, there is a need in the art for a masking material and process which reduces the labor hours required to mask and unmask an aircraft or the like while providing high quality masking. The present invention addresses this and other problems.